More water moved into and out of the atmosphere in 2000 than in 1950, making saltier parts of the world’s oceans saltier and fresher waters less salty, researchers report in the April 27 Science.

A warming planet may be to blame. Simulations in the new study suggest evaporation and rainfall got a 4 percent boost as surface temperatures rose half a degree Celsius. That boost is a bigger change than previous studies had suggested, but fits with the idea that a warmer atmosphere can hold more ...